> On Feb. 13, 2017, 9:49 a.m., Stephan Erb wrote: > > src/main/java/org/apache/aurora/scheduler/pruning/TaskHistoryPruner.java, > > lines 187-188 > > <https://reviews.apache.org/r/56575/diff/3/?file=1632276#file1632276line187> > > > > I am still not convinced this is really needed. For example, > > `MetricCalculator` doesn't have such a throttle either. > > > > Have you tested if those 10ms are sufficient and/or needed at all? How > > did you came up with this number?
I am afraid that this will start making less sense in the future, since there are no comments on how this value was chosen. Why don't we add this only if we need it, after performing a test? - Santhosh Kumar ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/56575/#review165356 ----------------------------------------------------------- On Feb. 13, 2017, 9:30 a.m., Mehrdad Nurolahzade wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/56575/ > ----------------------------------------------------------- > > (Updated Feb. 13, 2017, 9:30 a.m.) > > > Review request for Aurora, David McLaughlin, Santhosh Kumar Shanmugham, and > Stephan Erb. > > > Bugs: AURORA-1837 > https://issues.apache.org/jira/browse/AURORA-1837 > > > Repository: aurora > > > Description > ------- > > This patch addressed efficiency issues in the current implementation of > `TaskHistoryPruner`. The new design is similar to that of > `JobUpdateHistoryPruner`: (a) Instead of registering a `DelayExecutor` run > upon terminal task state transitions, it runs on preconfigured intervals, > finds all terminal state tasks that meet pruning criteria and deletes them. > (b) Makes the initial task history pruning delay configurable so that it does > not hamper scheduler upon start. > > The new design addressed the following two efficiecy problems: > > 1. Upon scheduler restart/failure, the in-memory state of task history > pruning scheduled with `DelayExecutor` is lost. `TaskHistoryPruner` learns > about these dead tasks upon restart when log is replayed. These expired tasks > are picked up by the second call to `executor.execute()` that performs job > level pruning immediately (i.e., without delay). Hence, most task history > pruning happens after scheduler restarts and can severely hamper scheduler > performance (or cause consecutive fail-overs on test clusters when we put > load test on scheduler). > > 2. Expired tasks can be picked up for pruning multiple times. The > asynchronous nature of `BatchWorker` which used to process task deletions > introduces some delay between delete enqueue and delete execution. As a > result, tasks already queued for deletion in a previous evaluation round > might get picked up, evaluated and enqueued for deletion again. This is > evident in `tasks_pruned` metric which reflects numbers much higher than the > actual number of expired tasks deleted. > > > Diffs > ----- > > src/main/java/org/apache/aurora/scheduler/pruning/PruningModule.java > 735199ac1ccccab343c24471890aa330d6635c26 > src/main/java/org/apache/aurora/scheduler/pruning/TaskHistoryPruner.java > f77849498ff23616f1d56d133eb218f837ac3413 > > src/test/java/org/apache/aurora/scheduler/pruning/TaskHistoryPrunerTest.java > 14e4040e0b94e96f77068b41454311fa3bf53573 > > Diff: https://reviews.apache.org/r/56575/diff/ > > > Testing > ------- > > Manual testing under Vagrant > > > Thanks, > > Mehrdad Nurolahzade > >
